Known is a device for supporting a rotatable spindle in an open-end spinning frame, which device comprises a spinning rotor, a spindle, one end of which is connected to the rotor and the other end of which has a whorl to be frictionally contacted with a high speed driving belt, a bearing casing for rotatably supporting the spindle, and a holder for holding the bearing casing therein. In the device, the movement generated by the high speed running of the belt is transmitted as a mechanical vibration to the holder via the spindle and the bearing casing, and accordingly, a noise is created.
Known is a device wherein resiliently yieldable members are sandwiched by a bearing casing and a holder so that the vibration is absorbed by the resiliently yieldable members. (See U.S. Pat. No. 3,874,751.) However, in the known device, the resiliently yieldable members are rigidly secured to the bearing casing by means of forced fitting or the like, and accordingly, when operational conditions, such as the rotational speed of the rotor, required changing, it is very troublesome to effect such changes because of the secured position of the resiliently yieldable members. In addition, since the air exhausting effect from the rotor is increased, and thus, the sucking effect generated by the vacuum within the rotor is also increased, as the rotating speed of the rotor increases, the bearing casing is subjected to the vacuum and leakage of the lubricant, such as a lubricating grease, within the bearing casing may be caused.
To obviate the leakage of the lubricant, known is a device wherein a labyrinth seal is formed at a space between the rotor and the bearing casing so that the rotor and the bearing casing are partitioned from each other by the labyrinth seal. However, in the known device, the resiliently yieldable members are formed independently from the labyrinth seal, and therefore, the construction of the spindle supporting device becomes very complicated.